diff --git a/scrapy/pqueues.py b/scrapy/pqueues.py
index ece0f9661..cf541c181 100644
--- a/scrapy/pqueues.py
+++ b/scrapy/pqueues.py
@@ -54,6 +54,7 @@ class ScrapyPriorityQueue(object):
 
     def qfactory(self, key, startprios=()):
         return self.downstream_queue_cls(self.crawler,
+                                         None,
                                          self.key + '/' + str(key),
                                          startprios)
 
diff --git a/scrapy/squeues.py b/scrapy/squeues.py
index 5d20c93d2..14bb0cb67 100644
--- a/scrapy/squeues.py
+++ b/scrapy/squeues.py
@@ -47,7 +47,7 @@ def _scrapy_serialization_queue(queue_class):
 
     class ScrapyRequestQueue(queue_class):
 
-        def __init__(self, crawler, key, startprios):
+        def __init__(self, crawler, downstream_queue_cls, key, startprios):
             self.spider = crawler.spider
             super(ScrapyRequestQueue, self).__init__(key)
 
@@ -70,7 +70,7 @@ def _scrapy_serialization_queue(queue_class):
 def _scrapy_in_memory_queue(queue_class):
 
     class ScrapyRequestQueue(queue_class):
-        def __init__(self, crawler, key, startprios):
+        def __init__(self, crawler, downstream_queue_cls, key, startprios):
             super(ScrapyRequestQueue, self).__init__()
 
     return ScrapyRequestQueue